XLT4 Agar

XLT4 Agar is used with Tergitol 4 for the isolation of non-typhi Salmonella spp. in a laboratory setting. XLT4 Agar is not intended for use in the diagnosis of disease or other conditions in humans.

Overgrowth of nuisance or contaminating organisms can be a major problem when recovery of a specific organism or species is desired. This is particularly true of Salmonella isolation media where overgrowth of Proteus, Providencia and Pseudomonas can dramatically interfere with the detection and isolation of Salmonella.

In 1990, Miller and Tate described a new medium, XLT4 Agar, for isolating Salmonella. Miller and Tate evaluated the sensitivity of the medium by detecting and isolating Salmonellausing fecal-contaminated farm samples containing high numbers of competing bacteria. In proceeding studies, Miller and Tate reported that XLT4 Agar significantly improved the recovery of non-typhi Salmonella from chicken and farm environmental drag-swab samples. XLT4 Agar can be used clinically to screen stool samples for non-typhoid Salmonella.

Formula

Liter

Enzymatic Digest of Animal Tissue

4.6 g

Xylose

3.75 g

L-Lysine

5 g

Lactose

7.5 g

Sucrose

7.5 g

Sodium Chloride

5 g

Yeast Extract

3 g

Phenol Red

0.08 g

Ferric Ammonium Citrate

0.8 g

Sodium Thiosulfate

6.8 g

Agar

15 g

Final pH: 7.4 ± 0.2 at 25°CFormula may be adjusted and/or supplemented as required to meet performance specifications.

Supplement (7990)

XLT4 Supplement, 100 mL

Directions

Suspend 59 g of the medium and 4.6 mL of XLT4 Supplement (# 7990) in one liter of purified water.

Heat with frequent agitation and boil for one minute to completely dissolve the medium.